Bucket for elastic-fluid turbines.



' 'PATENTEDJUNE 26,1906. AHLQUIST. -BUCKET FOR ELASTIC APPLICATION FILE No. s24,52-1. 1

FLUID- TURBINES; D NOV. 28 190 Unrrnn stra ns ATENT orrron KARL AHLQUIST, OF RUGBY, ENGLAND, ASSIG'NOR TO GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW roar;

BUCKET FOR ELAsTio-FLum renames.

Specification of Letters Patent. Application filed November 28, 1905. Serial No. 289,52.

r. Jnted June 26,1906

To all whom it may concern.-

Be it known that'l, KARL AHL UIsT, a subject of the King of Sweden, residing at Sunnyside, Clifton Road, Rugby, En land,'have invented certainnew and usefu Improvemeets in Buckets'for Elastic-Fluid Turbines, of which the following is a s ecification.

The present invention re ates to the construcfion of buckets for elastic-fluid turbines,

more especially those of the axial and radial flow types, and has for its ob'ect to provide an improved form of bucket w ereby such tur bines may be operated with greater efficiency than heretofore.

, In order to enable the maximum amount of energy to be abstracted from the fluid in elastic-fluid turbines, it is necessary that the bucket-angles on the discharfie side shall be small. In turbines as usua y constructed this condition cannot be fulfilled on account of the difliculty in providing sufficient outlet area for the fluid. I It has therefore been found necessary to employ buckets having a relatively large angle of delivery.

Accordin to my invention the abovementioned ifiicultv is obviated by providing example, this result may be obtained by niaking each bucket in a row of a spherical orcup's.

shape.

For a fuller and detailed description of my invention attention is directed to the description and claims appended thereto.

In the accompanying drawings, represent ing one embodiment of the invention, Figure 1 IS a rear erspectiveviewof two adjacent turbine-budlrets, together with a support therefor. Fig. 2 is a front perspective view of the same buckets.

through the center of the buckets. 4 is a lon itudinal section through the buckets,

and ig. 5 is a partial rear elevation of one of the buckets.

I construct the vane or bucket spaces by providing a number of cup-shaped buckets 1, which. are nested or arranged one within the other at a suitable distance apart around the turbine-wheel or other support 2. Each Fig. 3 isa cross-section bucket isprovided with a shank 3, having outwardly-eXtendin shoulders 4 formed thereon. One of t ese shoulders engages with an annular flange 5, formed integral with the su port, and the other engages with a removabl .annular flange bolte or otherwise secured to the support. Between the removable annularflange and the support is a shoulder 6, Which takes the centrifugal strains off of the securing devices.

In order to form a fluid-space between therators 7 and 8, formed integral therewith, the former being inte al with the back-or con vex portion ofthe. 'ucket, and the latter with ,the shank. The'cnds of these separators are convex, so as to make a good fitiwith the con- In addition to actin .as separators, the opposed faces of these distance-pieces are divergent,and so shaped as to form,with the bucketwalls, an ex anding passage from the inlet to the exit. n order' to provide a lesser exit than entrance-a le' for-the fluid, assuming that each bucket as its interior and exterior surfaces of the formof two concentric hemiangles to the axis of thewheel or sup ort containing willdivide them uns, etrical Instead, however, of the back or convex surface of .each bucket-being hemispherical it may be iven a paraboloidal form, the portion of t e .curve on theexitside of the axis of the paraboloid being longer than on the inlet side.

.- The type of bucket shown is intendedprirnarily for use in a multistage machine havin Wien applied to a multistage machine having stage, it would generally be used only on'the low-pressure end, since it is with these buckets t at the greatest difiiculty is experienced in extracting the proper amount of energy from the steam.

In' accordance with the provisions of the patentstatutes I have described the princispheres, it is turned or-twistedsomewhat with respect to its shank,'s'o that a plane at right I the'centers of the-hemisp eres in-"- stead of dividing the buckets symmetrically y, and radial lanes containin t ecircular edge of eachucket instead 0 passingi'through the axis of the wheel will cut the said axis at an angiey a single row of wheel-bucketsper stage.

buckets, the backof each bucket isprovided with upper and lower distance pieces or sep'acave or working face of the adjacent bucket.

more than a single row of wheel-buckets per ple of operation of my invention, together with the apparatus which now consider to represent the best embodinient thereof; but I desire to have it understood that the apparatus shoivn is only illustrative and that the invention can be carried out by other means.

What I claim as new, and desire to secure by Letters Patent of the United States, is-

1 In a turbine, the combination of a support, individual cup-shaped buckets carried thereby, and diverging distance-pieces between the buckets which are so shaped and positioned as to form with the buckets agradually-expanding fluid-passage.

2. In a turbine, the combination of a support, a plurality of independent cup-shaped buckets carried thereby, and distance-pieces i'ormed integral with the buckets, which are provided with convex end surfaces arranged to fit the concave surface of the adjacent bucket.

In a turbine, the combination of a sup- 5 port, a plurality of inde )endent cup-shaped that the entrance-angle of the bucket is.

greater than the exit-angle, and pieces between the buckets which serve to space the buckets apart and are so shaped as to form a pa rt of the expanding passage for the fluid.

5. In a turbine, the combination of a support, a plurality of cup-shaped buckets carried thereby, shanks for the buckets, a shoulder betn-een the support and the shanks for securing" the buckets in place. and d iverging, distance-pieces carried by each bucket, and arranged to it the concave surface of the ad ptcent bucket.

- In witness whereof I have hereunto set my hand this 15th day of Xovember, 19.05.

KAR 11 All I QUIS'l.

. itnesses:

ERNEST MARKER, SIDNEY Geo. \VEBB 

